1. Field of the Invention
The present invention relates to a portable electrocardiograph capable of providing electrocardiographic data on a patient with no need to constrain the patient to the examination room.
2. Description of the Prior Art
The conventional electrocardiographic system comprises a display unit for the display of an electrocardiographic wave. The display unit used in combination or association with the electrocardiographic system is not provided with any calibrated scales which would facilitate a physician or technician to comprehend the size and/or movement of the electrocardiographic wave being displayed. The lack of the calibrated scales on the display unit has hitherto provided a problem in that a medical examination of the heart of a patient cannot be performed as correctly and quickly as possible with no difficulty.
The electrocardiographic system comprising a display unit employed in the form of a cathode ray tube (CRT), a keyboard having a plurality of input keys and a main body having a central processing unit built therein. In such prior art electrocardiographic system, some of the keys on the keyboards are required to be manipulated so that information concerning the type and level of a patient's symptom and a treatment can be inputted to the central processing unit. The manipulation of the keyboard for this purpose is not easy unless the physician or technician has an appropriate knowledge in addition to the knowledge of particulars in his or her major field of business.
Also, where an electrocardiographic recording is to be routinely made with the use of the electrocardiograph, the inputting of information connected with conditions under which an ECG measurement is carried out such as the type and level of the patient's subjective symptom and the pattern of behavior of a patient during the actual measurement appears to be feasible in that the accurate determination of the electrocardiogram so recorded can be accomplished. However, the prior art electrocardiographic system is of a construction comprising a main body which is separate from a main body of the electrocardiographic apparatus and which is provided with changeover switches generally equal in number to the possible number of the measurement conditions such as the number of patterns of behavior and the number of types of the subjective symptoms, a multi-event operating unit through which information connected with the pattern of behavior and the type of subjective symptom can be inputted to the main body, and a number of cords corresponding to the number of the changeover switches used for connecting the multi-event operating unit with the main body. Because of this, the prior art electrocardiographic system tends to be bulky in size enough to impose a load on a patient who is the user of the electrocardiographic system.
Moreover, in the prior art electrocardiographic system, a power switch, a start/stop switch and some other switches such as event markers are exposed to the outside, protruding outwardly from the casing. Therefore, where the prior art electrocardiographic system is transported, the patient carrying the system may erroneously manipulate one or more of the switches. Once one or more switches are erroneously manipulated during the measurement taking place, a loss of information recorded for a substantial length of time will take place.